50 miles east. because the 30 miles north then south cancel each other out.
Answer:
C)Before leaving for their trip, turn the central heating system off, along with lights and electrical household appliances.
Explanation:
Although, the other three options will also reduce their electricity bill but they do not explain why Mr. Hernandez's family got same electricity bill as last year even though this time they were not home for one and a half week. Also, A), B) and D) ideas are not reasonable.
So, the only conclusion is that even when they were on a vacation. the electrical appliances in their home were on. That's why the bill remained the same.
The idea of turning the central heating system off, along with lights and electrical household appliances before they leave for the trip will help reduce the energy usage. Also, it is reasonable.
Answer:
The efficiency of the engine is 59.2%.
Explanation:
We have,
Work done by the gasoline engine is 45 J and the for every 76 J of heat it takes in.
It is required to find the efficiency of the engine. Efficiency of the engine is given by the ratio of work done to the heat taken i. Its formula is given by :

So, the efficiency of the engine is 59.2%.
Answer:
Star characteristics consider physical characteristics such as stellar mass, size, surface temperature, and luminosity .
<span>Length that is distance s = 4.00m
Speed of sound in air V = 343 m/s
Time for metal = 11.0ms = 0.011
Calculating the time t = s / V = 4 / 343 = 0.01166s
Time for the sound in the metal = 0.01166 - 0.011 = 0.00066 = 6.6 x 10^-4s
Speed of sound in metal Vm = 4 / 6.6 x 10^-4 = 6.060 x 10^3 m/s</span>